Everything to Know About Titanium Dioxide, a Main Ingredient In Physical SPF

Sunscreen should be a no-skip step in everyone's skin-care routine. Protecting yourself from the sun's harmful rays is not only essential for the aesthetic appearance of your skin, but also its health. Over time, exposure to UV rays can cause discoloration, wrinkles, and even skin cancer.

As for how sunscreens keep you safe, they contain either chemical UV blockers or mineral (aka physical) ones. Chemical sunscreen formulas typically use avobenzone and oxybenzone as their main ingredients, which get absorbed into the skin, thus absorbing the sun's rays and protecting your skin. With physical sunscreen, a natural compound like zinc oxide or titanium dioxide sit on top of the skin, physically blocking the ultraviolet light from being absorbed into the skin (more on that later).

So how do you know which to choose? We tapped a dermatologist to help us understand the main ingredient in physical sunscreen: titanium dioxide.

If you think back to chemistry class and the periodic table, you'll recall that titanium is an element found in the earth's crust. "Chemical sunscreens are carbon-based compounds," dermatologist Joshua Zeichner, MD, associate professor of dermatology at Mount Sinai Hospital in New York City, tells POPSUGAR. "Physical blockers are made of minerals, and since they don't have any carbon atoms in them, they are technically called inorganic compounds."

Titanium dioxide is used as a white pigment in everything from toothpaste to cake decoration. Sunscreen uses ultra-fine titanium dioxide particles that create a transparent barrier to the sun's rays.

"It is a common misconception that mineral sunscreens sit on the surface of skin and work solely by reflecting light away like a suit of armor," Dr. Zeichner says. "In fact, there is strong data showing that titanium dioxide actually absorbs UV light as much as it reflects it." That means that the mineral blocker not only acts like a mirror bouncing harmful UV rays off of skin but also soaks them up so your skin doesn't.

The only downside is that mineral sunscreens tend to leave a white cast on skin, especially for those with more melanated skin. Thankfully, companies have been working on this, and many new formulas are more elegant and less visible. Products like Cetaphil Sheer Mineral Sunscreen Lotion SPF 50 for Face and Body ($15) and La Roche-Posay Anthelios Mineral Sunscreen Gentle Lotion Broad Spectrum SPF 50 ($32) are formulated to be virtually undetectable, and SkinCeuticals Physical Fusion UV Defense SPF 50 ($42) and Supergoop Mattescreen SPF 40 ($38) have tints to them to help minimize any white appearance.

Cetaphil Sheer Mineral Sunscreen Lotion SPF 50 for Face and Body

From

$11

$11 at Amazon

La Roche-Posay Anthelios Mineral Sunscreen Gentle Lotion Broad Spectrum SPF 50

From

$31

$31 at Amazon

SkinCeuticals Physical Fusion UV Defense SPF 50

From

$36

$36 at Dermstore

Supergoop Mattescreen SPF 40

From

$38

$38 at Sephora

Yes, titanium oxide is safe — the FDA classifies it as GRASE or Generally Recognized as Safe and Effective. "Mineral sunscreens tend to be less irritating to the skin, so they are often preferred by those with sensitive skin," says Dr. Zeichner.

In general, physical sunscreens containing titanium dioxide are suitable for all skin types and are also safe to use on babies and during pregnancy. They are typically noncomedogenic, which means people with acne-prone and oily skin can use them.